Chemical, Antioxidant, and Antimicrobial Properties of the Peel and Male Flower By-Products of Four Varieties of Punica granatum L. Cultivated in the Marche Region for Their Use in Cosmetic Products

Pomegranate peels and male flowers are not waste—they are a treasure trove of bioactive compounds that could revolutionize cosmetics. A new study reveals these by-products are packed with antioxidants and antimicrobial power, offering a greener path for beauty products.

The growing mountain of agri-food waste is turning into a goldmine for natural cosmetics. Researchers in Italy's Marche region have now turned their attention to pomegranate by-products—specifically, the peel and, for the first time, the male flowers—of four varieties: Wonderful, Mollar de Elche, Parfianka, and the lesser-known G1. Their goal? To find innovative, eco-friendly ingredients that can replace synthetic additives in skincare.

Using advanced UPLC-ESI-MS/MS, the team identified a spectrum of phenolic compounds, from hydrolysable tannins to anthocyanins. The stars were punicalagin isomers and punicalin, especially abundant in the peel and male flower extracts. Notably, Mollar de Elche 2020 peel extract boasted high levels of punicalagin A and B (7206.4 and 5812.9 mg/kg), while G1 and Parfianka excelled in gallic acid.

When tested for antioxidant capacity, the peel extracts outperformed the male flowers, thanks to their punicalagin content. Mollar de Elche 2020 peel extract hit the highest total phenol content at 12.341 µmol GAE/g. Meanwhile, antimicrobial tests showed that Wonderful and G1 2020 peel extracts were active against Escherichia coli, and all extracts showed promising anticandidal activity. Crucially, none of the extracts were toxic to skin cells (HaCaT keratinocytes) at concentrations up to 5.00 mg/mL, making them safe candidates for cosmetic formulations.

This research paves the way for turning local agricultural waste into valuable, natural cosmetic boosters—a win for both sustainability and skin health.

Key Points

• Pomegranate peel and male flower extracts are rich in bioactive compounds.
• Mollar de Elche peel shows highest antioxidant capacity and phenol content.
• Extracts non-toxic to skin cells and active against E. coli and Candida.